But basically has anyone ever taken the VGA and DVI leads from ONE monitor and plugged them into TWO DIFFERENT machines both powered on? Then tried switching between DVI and VGS modes on their monitor to "toggle" between the machines? If that would work for me it would be pretty neat....

As long as you have a switch that determines which feed is active on the monitor there should be no problem connecting two different machines since the monitor will only be receiving one feed at a time.

A friend of mine had this setup on his Dell computer and screen plus his server (som old IBM or something). It worked very well without any KVM switch. The desktop was connected via DVI and the server via D-sub (VGA as you say). He could select computer with a button on the screen that changed between DVI and D-sub. The mouse and keyboard however is still tied to one computer of course.

I have a similar button on my screen (Hercules 920 Pro DVI), but since I only have one connector (DVI-I) on the screen I will need a splitter cable before I could try it.

Esp. Zedric - I shall try it now soon enough, there will not be so much room for my feet under the tiny desk I have but it will be worth it for the transition - and I shall post here of course on the outcome

OK got it working now - think it was something to do with having not conjnected all my IDE devices (God only knows why - both masters were on).... Basically been building my new AMD64 system today and found I am an IDE short - went back to my PII and stole an old one while waiting so that I could boot machine and get on with format - that is running now while I am using the DVI mode It's neat but can get confusing with all the keyboards and stuff